Problem-based learning, often abbreviated as PBL, is a student-centered method of teaching in which students are encouraged to think their way through complex problems. Rather than an instructor simply "doling out” information to students as something to be consumed by them, the instructor acts more as a facilitator who helps groups of students to cooperatively work their way through and eventually solve the problem.

Proponents of problem-based learning point to numerous studies that show PBL leads to a higher quality of learning. Detractors, on the other hand, cite other studies showing that PBL early in the learning process is actually less effective than traditional instructional strategies.

In this article, we'll take a closer look at what problem-based learning is, what its benefits and shortcomings are, and how to begin to implement problem-based learning in a classroom environment.

What is Problem-Based Learning?
Typically, problem-based learning begins by dividing the class into groups of about five students. Generally speaking, the membership of each group remains the same throughout the term or semester. The instructor provides the students with a problem to solve, but it is up to the students to discern what they already know, what they need to know, and how they will find the new information that will lead to a solution of the problem.

Once the students decide what it is they need to know in order to solve the problem, their study is primarily self-directed, drawing upon books, journals, online information, reports, and local experts to fill in the gaps in their knowledge. Having gained the information they need, the students then apply that information to the problem and create a solution. At the end of the process, most problem-based learning programs require that the students engage in a self-evaluation of themselves and their peers to better understand what they learned and what they could improve the next time.

The instructor's role in problem-based learning is a tricky one. The instructor is to "facilitate” learning without giving students the answer outright. Instructors who experiment with problem-based learning in their classrooms find that understanding how to guide the students without giving the answer, but also without hiding the answer, requires a finesse and commitment to the process that traditional teaching does not demand.

The Pros and Cons of Problem-Based Learning
Overall, problem-based learning is a superior method of both teaching and learning that demands of the students a higher degree of participation, cooperation, and development of critical-thinking skills. Because PBL is primarily self-directed or at least peer-directed, students take a much more active role in their own education and are typically more motivated to learn. Furthermore, because problem-based learning provides complex, real-world problems and requires students to work together in groups, students gain practical skills that closely mirror both the knowledge and the social interaction they will encounter once they become professionals in their fields.

The benefits of PBL can be summarized as producing professionals who:

Are equipped with critical-thinking skills

Are prepared to work cooperatively

Understand the need for continuously improving their education

Problem-solve effectively

Are capable of self-assessment and course correction

The downside of problem-based learning is the relative difficulty problem-based learning presents for students who are new to the subject. For example, students who are new to algebra may not be able to use the problem-based learning method effectively when they are first introduced to the subject. Instead, studies have shown that the new algebra students learn faster when they study worked examples as a first step

Implementing Problem-Based Learning in the Classroom
How problem-based learning is actually implemented in the classroom will naturally vary based on the age of the students, the subject being studied, and the pre-requisite knowledge. In all instances of classroom implementation, it helps to keep in mind the basic structure of a problem-based learning unit:

Step 1 is to introduce the problem. At this stage, student groups will clarify the facts, determine what they need to learn, and plan how they will find the information they need.

Step 2 is the stage of self-directed learning, in which students engage individually and/or as a group in the process of gathering the information they need to solve the problem.

Step 3 the students meet as a group to review the information they have obtained and apply the new information to the problem, synthesizing a solution.

Step 4 will vary depending upon the subject and instructor preference, but will consist of the students demonstrating what they have learned in the form of a report, presentation, test, or some combination thereof.

Step 5 is the final step, in which students evaluate themselves and each other, determining how well they did and identifying what they could have done better.

All of these steps can be easily modified to suit the needs of the subject being studied and the students.

Some teachers use a mixed approach, combining PBL with other forms of instruction. For example, some college instructors intersperse traditional lectures with PBL group meetings, thus alleviating the problem identified above.

In sum, problem-based learning is a highly effective pedagogic technique that leads to students who are both self-directed and capable of applying concepts to solve a variety of problems. Motivated to learn and ready to use teamwork to solve problems, PBL produces professionals who are already prepared to work with others in order to solve complex problems.